As shown in FIGS. 1 and 2 of the attached patent document, a lifting track of curtain of the prior art consists of a cord B for holding the curtain. The curtain can not be lowered or lifted in a uniform manner in view of the fact that the cord B can not be wound regularly on a cord-winding shaft A. The Taiwanese Patent Publication No. 168230 discloses a lifting track to overcome the drawback of the prior art lifting track of curtain described above. The second prior art lifting track of curtain consists of a cord-winding shaft 30 which is provided in the periphery thereof with threads and a guiding member 40 fastened with the shaft 30 such that the guiding member 40 is capable of a translational motion at the time when the cord-winding shaft 30 turns. The shaft 30 is further provided with a plurality of locating members 50 to serve as locating points at the time when the curtain is lowered or lifted. When the cord-winding shaft 30 turns, the cord 33 is guided by the guiding member 40 to wind on the shaft 30 in a regular manner. The second prior art described above is complicated in construction and is not cost-effective.